Guide: Soft starters for electric motors

This guide introduces the basic principles of soft starters and highlights the most important benefits of using a soft starter for various types of applications.

The first step toward success is making the right start. When designing an application, it is always worth considering exactly what happens when you start the electric motor. A soft starter provides a better start, avoiding overvoltages and sudden movements. Soft starters also allow applications to perform a soft stop.

Electric soft starters operate by sending voltage through a series of connected semiconductors. During a soft start, these components can be configured to gradually allow an increasing amount of current to pass through. By reversing the process, it is possible to gradually reduce the voltage, which ultimately brings the motor to a soft stop.

What is a soft starter and why is it essential for your electric motors?

Understanding what a soft starter is and its pivotal role in the operation of electric motors can be a game-changer for businesses looking to enhance efficiency and protect their equipment.

Unlike traditional starting methods such as Direct-On-Line (DOL) and Star-Delta, which can cause power spikes and excessive mechanical stress, a soft starter smoothly controls the acceleration and deceleration of electric motors. This not only prevents abrupt power surges but also significantly reduces the wear and tear on motor components, making it an essential tool for extending the lifespan of your motor-driven applications.

How does a soft starter work to enhance motor performance?

The magic of how a soft starter works lies in its ability to finely regulate the voltage and current supplied to the motor during the start-up phase. This gradual increase in power ensures a smooth start, which in turn, controls the inrush current and minimises mechanical strain on the system. By adjusting the voltage, soft starters allow for a controlled acceleration, significantly reducing the risk of damage and downtime. This process is crucial for maintaining optimal performance and reliability of motor applications, making soft starters an indispensable part of modern motor control technology.

The advantages of implementing soft starters

Implementing soft starters brings a host of advantages that contribute significantly to the operational efficiency and reliability of motor-driven systems in many industries and applications:

Better application control: In applications such as pumps and centrifugal fans, soft starters play a crucial role in mitigating risks associated with water hammering. This controlled start-up and shutdown process prevents sudden pressure surges, protecting the system from potential damage.

Preventing power spikes: By smoothing out the initial power demand, soft starters help maintain grid stability and ensure operational efficiency. This is particularly important in sensitive environments like marine applications, where power quality can directly impact operational reliability and safety.

With these advantages, it's clear why the motor soft starter market is rapidly expanding, as industries recognise the value of soft starters in protecting their investments and optimising their operations.